Endless articulated conveyor movable in a three-dimensional curved path

ABSTRACT

An endless conveyor belt has a plurality of link members interconnected so that the conveyor belt is movable along a path (22) curved essentially in the plane of the conveyor belt and also about a guide roller whose axis is parallel to the plane of the conveyor belt. Product carriers (17) are supported successively by the link members and are essentially rigid in the plane of the conveyor belt; however, they are movable, together with the conveyor belt, about the guide roller. Each product carrier is longer, in the longitudinal direction of the extension of the conveyor belt, than each link member.

BACKGROUND

The present invention relates generally to conveyor belts, morespecifically to endless conveyor belts comprising a plurality of linkmembers, which are interconnected in such manner that the conveyor beltis movable along a curved path essentially in the plane of the conveyorbelt and is also movable about a guide roller.

Such conveyor belts are disclosed in, for example, U.S. Pat. Nos.3,938,651, 4,603,776 and 4,941,567. What the conveyor belts according tothese publications have in common is that they consist of link memberswith side links, which permit the conveyor belt to follow a helicalpath, in which a superjacent conveyor belt part is directly supported bya subjacent conveyor belt part.

Other examples of conveyor belts of the type mentioned by way ofintroduction are disclosed in U.S. Pat. Nos. 3,225,893, 3,261,451 and4,875,343. Also these conveyor belts can follow a helical path but arethere at least on one side supported by separate supporting rails.

Regarding the above-mentioned conveyor belts, it is a general rule thatthe transition between a straight path and a curved path forces anextension of the conveyor belt on its one side and/or a shortening ofthe conveyor belt on its other side. This causes a relative motionbetween at least parts of the upper side of the conveyor belt andproducts carried by this upper side. Owing to this condition, certainproducts, such as pieces of dough, are difficult to transport by meansof such a belt conveyor.

SUMMARY OF THE INVENTION

The object of the present invention therefore is to provide a conveyorbelt of the type mentioned by way of introduction, which despite thecapacity of being movable alternatingly along straight and curved pathsshould be usable for transport of such products as do not withstand anymovement relative to the supporting base of the conveyor belt.

By arranging, according to the invention, a plurality of such productcarriers, very fragile products can be moved by a conveyor belt alongstraight as well as curved paths and, in transitions between these,without any relative motion arising between the products and thesupporting surfaces of the conveyor belt. To this end, the inventionthus uses product carriers which in turn are supported successively bythe link members, are essentially rigid in the plane of the conveyorbelt, but moveable together with the conveyor belt about the guideroller, and each have a greater length in the longitudinal direction ofthe conveyor belt than each link member.

In its preferred embodiment, each product carrier has a length in thelongitudinal direction of the conveyor belt which is at least as greatas the length of two links members. Moreover, at its front part in thetravelling direction of the conveyor belt, each product carrier isconnected to its link member. The front part of the product carrier hasessentially the same width as the link members, and the product carriertapers backwards so as not to protrude beyond the link members along thecurved path.

In one embodiment, the movability of the product carriers about a guideroller can be achieved by each product carrier being formed of aplurality of elements, which are articulated to each other transverselyof the longitudinal direction of the conveyor belt. Each such elementcan have a length in the longitudinal direction of the conveyor beltwhich essentially corresponds with the length of a link member. Thelength of the element can also be smaller than the length of the linkmember, but not essentially greater than this.

In a further embodiment, each product carrier consists of a singleelement, for instance a fabric-like material, such as a cloth or a net,which is essentially rigid in its own plans, such that when pressingtogether or extending the link members in the plane of the conveyorbelt, it moves merely relative to these link members. Consequently, norelative motion occurs between the fabric-like material of the productcarriers and the products supported thereby.

The invention will now be described in more detail with reference to theaccompanying drawings, in which:

FIG. 1 is a perspective view of a conveyor belt, to which the presentinvention is applicable;

FIG. 2 is a perspective view of part of the conveyor belt in FIG. 1 on alarger scale;

FIGS. 3A-C are schematic side views of an embodiment of a conveyor beltaccording to the present invention; and

FIG. 4 is a top plan view of part of the conveyor belt in FIGS. 3A-C ina belt stack according to FIG. 1.

DETAILED DESCRIPTION

The conveyor belt 1 shown in FIGS. 1 and 2 consists of a plurality oflink members 2. Each link member 2 consists more specifically of tworods 3 and 4 extended transversely of the longitudinal direction of thebelt and fixedly interconnected on each side of the conveyor belt bymeans of side links 5, 6 in the form of plates. The side links 5, 6 ofeach link member 2 each overlap a corresponding side link 5, 6 of one ofthe two neighbouring link members 2.

The side links 5, 6 have flanges 7 and 8 at the bottom, such that aportion of the conveyor belt 1 can be supported by a subjacent portionof the same conveyor belt 1. This is the case, for example, in FIG. 1where the conveyor belt 1 along part of its length follows a helicalpath and forms a stack 9, in which each turn of the conveyor belt 1,except the lowermost turn, is supported by a subjacent turn of theconveyor belt 1. The link members 2 are interconnected in such mannerthat the conveyor belt 1 is movable along a curved path essentially inthe plane of the conveyor belt, such as in the stack 9, and is alsomovable about a guide roller, for example transverse guide rollers10-13, over which the conveyor belt 1 travels from the point of leavingthe stack 9 until reentering the stack 9. This movability is achieved bymeans of holes 14, 15 in each side link 5, 6, through which holes 14, 15extends the transverse rod 4 of a neighbouring link member 2. The hole14 is shown as a hole which is elongate in the longitudinal direction ofthe conveyor belt 1, which means that the two side links 5interconnected by means of the hole 14 and the transverse rod 4 areoffset relative to each other in the longitudinal direction of theconveyor belt 1 and turnable relative to each other about the transverserod 4. The hole 15 is circular and therefore permits only rotation ofthe side links 6 relative to each other about the transverse rod 4.

It will be appreciated that the holes 14 and 15 can change places, orthat the hole 15 can have the same appearance as the hole 14. Therelative position of the hole 14 and the transverse rod 4 in thelongitudinal direction of the conveyor belt 1 is decisive of thepossibility of moving the side links 5 towards or away from each other,or towards as well as away from each other. Depending on this mutualposition, the conveyor belt 1 can, when passing from a straight path toa curved path, be subjected to merely a pressing-together at the innerside of the curved path or merely an extension at the outer side of thecurved path, or be subjected to a pressing-together at the inner side aswell as an extension at the outer side. In all cases, however, arelative motion will take place between each pair of neighbouring linkmembers 2. The zigzag wires which usually enclose two or threeneighbouring transverse rods in the prior-art conveyor belts of the typedescribed above will then also move relative to each other.

FIG. 3 is a schematic side view of the conveyor belt 1 as part of anembodiment of the present invention. The side links 5 or 6 are thus veryschematically shown as longitudinal rods 16, each fixedly connecting apair of transverse rods 3, 4 to each other. For the sake of simplicity,the holes 14, 15 of the side links 5 or 6 have thus been omitted.

FIG. 3A shows the conveyor belt 1 with the link members 2 inpressed-together or not separated state, i.e. the appearance of theconveyor belt 1 along a straight path or on the inside of a curved path.A product carrier 17 is fixed to every third link member 2, Each productcarrier 17 has three slate 18, which are articulated to each other aboutpins 19, which along the straight path are parallel to the transverserods 3, 4. Each slat 18 extends across the conveyor belt 1 and thus isof essentially rectangular shape. Moreover, it is substantially rigidand is preferably foraminous so as to allow air to pass therethrough.

The fixing of the product carrier 17 to one of the link members 2 isaccomplished by the fact that the slat 18, which is the foremost one inthe travelling direction of the conveyor belt 1, comprises flanges 20,by means of which the slat 18 can be snapped on over the transverse rods3, 4 to the link member 2.

The length of each slat 18 in the longitudinal direction of the conveyorbelt 1 conforms with the centre distance between the link members 2 inFIG. 3A, i.e. each slat 18 has substantially the same length as one ofthe link members 2.

FIG. 3B illustrates the conveyor belt in FIG. 3A in extended or notpressed-together state along a straight path or along the outside of thecurved path, in which latter case the Appearance of the conveyor belt 1is shown merely along the actual outside of the curved path. As appearsfrom FIG. 3B, the three slats 18 of the product carrier will besupported in a plane position, unchanged relative to the position inFIG. 3A, by two of the link members 2, which are moved apart relative tothe position in FIG. 3A at least along the outer side of a curved path.

FIG. 3C shows the conveyor belt 1 in FIGS. 3A and 3B in extended or notpressed-together state along a path about a guide roller (not shown),e.g. one of the guide rollers 10-13 in FIG. 1. Here the product carrier17 can accompany the conveyor belt 1 about the guide roller essentiallyin contact with the conveyor belt 1 thanks to the slats 18 beingarticulated to each other about the pins 19, which also in FIG. 3Cextend parallel to the transverse rods 3, 4.

FIG. 4 illustrates the conveyor belt 1 according to FIG. 3 in a top planview along a turn in such a stack as the stack 9 in FIG 1. Along astraight path 21, the product carriers 17 take the same position asshown in FIG. 3A, while along a curved path 22 inside the stack, theyhave been offset relative to the two link members 2 which support eachproduct carrier 17 but which are not fixed relative to the productcarrier 17. This relative motion is a consequence of the fact that thelink members 2 supporting the product carrier 17 are either moved apartat the outer side of the curved path, as is the case in FIG. 4, or arepushed together at the inner side of the curved path.

In the embodiment of the inventive conveyor belt as shown in FIGS. 3 and4, the product carriers are directly supported by the transverse rods 3,4. The zigzag wires which in the known conveyor belt surround thetransverse rods 3, 4 are thus not necessary but may be arranged on theinventive conveyor belt.

If the conveyor belt has the above-mentioned zigzag wires, a cloth or anet, or some other fabric-like material of metal, plastic or textile, ora flexible sheet can be used instead of the product carriers 17.

To prevent the product carriers 17 or other equivalent product carriersfrom protruding beyond subjacent parts of the conveyor belt 1 alongcurved paths, they taper backwards, as shown in FIG. 4, in case thecurved paths require that the belt turn in one direction only.

Many modifications of the above-described embodiment of a conveyor beltare possible within the scope of the invention, as defined in theaccompanying claims.

I claim:
 1. An endless conveyor belt movable about a guide rollertransverse to a longitudinal direction of the conveyor belt; theconveyor belt comprising:a plurality of interconnected link members (2),the conveyor belt (1) being movable along a curved path (22) essentiallyin a plane of the conveyor belt and also about the guide roller (e.g.10); and a plurality of product carriers (17), which are successivelysupported upon the link members (2), are essentially rigid in the planeof the conveyor belt (1), which are movable together with the conveyorbelt about the guide roller (e.g. 10), and each having a greater lengthin the longitudinal direction of the conveyor belt than each linkmember.
 2. The conveyor belt as claimed in claim 1, wherein the productcarriers are not mutually interconnected.
 3. The conveyor belt asclaimed in claim 1, characterised in that in its front part in thetravelling direction of the conveyor belt (1), each product carrier (17)is connected to its link member (2).
 4. The conveyor belt as claimed inclaim 3, characterised in that the front part of the product carrier(17) has essentially the same width as the link members (2), and thatthe product carrier tapers backwards so as not to protrude beyond thelink members along the curved path.
 5. The conveyor belt as claimed inclaim 12, characterised in that each rigid element (18) has essentiallythe same length in the longitudinal direction of the conveyor belt (1)as one of the link members (2).
 6. The conveyor belt as claimed in claim1, characterised in that each product carrier is made of a materialwhich is essentially rigid in its own plane.
 7. The conveyor belt asclaimed in claim 1, characterised in that the curved path (22) is ahelical path.
 8. The conveyor belt as claimed in claim 7, characterisedin that each link member (2) comprises side links (5, 6) which areoffset relative to each other in the longitudinal direction of theconveyor belt (1) at least at the outer edge of the helical path (22).9. The conveyor belt as claimed in claim 8, characterised in that theside links constitute spacer members for supporting a superjacent partof the conveyor belt.
 10. The conveyor belt as claimed in claim 1,characterised in that the length of each product carrier (17) in thelongitudinal direction of the conveyor belt (1) is at least as great asthe length of two link members (2).
 11. The conveyor belt as claimed inclaim 2, characterised in that each product carrier (17) consists of aplurality of rigid elements (18) which are articulated (19) to eachother traversely of the longitudinal direction of the conveyor belt (1)to permit the product carrier to move together with the conveyor beltabout the guide roller (e.g. 10).
 12. The conveyor belt as claimed inclaim 10, characterised in that the front part of the product carrier(17) has essentially the same width as the link members (2), and thatthe product carrier tapers backwards so as not to protrude beyond thelink members along the curved path (22).
 13. The conveyor belt asclaimed in claim 12, characterised in that each product carrier is madeof a material which is essentially rigid in its own plane.
 14. Theconveyor belt as claimed in claim 12, characterised in that each productcarrier (17) includes a plurality of rigid elements (18) which arearticulated (19) to each other transversely of the longitudinaldirection of the conveyor belt (1) to permit the product carrier to movetogether with the conveyor belt about the guide roller (e.g. 10). 15.The conveyor belt as claimed in claim 14, characterised in that eachrigid element (18) has essentially the same length in the longitudinaldirection of the conveyor belt (1) as one of the link members (2). 16.The conveyor belt as claimed in claim 12, characterised in that eachproduct carrier is made of a material which is essentially rigid in itsown plane.
 17. The conveyor belt as claimed in claim 16, characterisedin that the curved path (22) is a helical path.
 18. The conveyor belt asclaimed in claim 17, characterised in that each line member (2)comprises side links (5, 6) which are offset relative to each other inthe longitudinal direction of the conveyor belt (1) at least at theouter edge of the helical path (22).
 19. The conveyor belt as claimed inclaim 18, characterised in that the side links constitute spacer membersfor supporting a superjacent part of the conveyor belt.
 20. An endlessconveyor belt movable about a guide roller transverse to a longitudinaldirection of the conveyor belt; the conveyor belt comprising:a pluralityof interconnected link members (2), the conveyor belt (1) being movablealong a curved path (22) essentially in a plane of the conveyor belt andalso about the guide roller (e.g. 10); and a plurality of productcarriers (17), which are successively supported upon the link members(2), are essentially rigid in the plane of the conveyor belt (1), whichare movable together with the conveyor belt about the guide roller (e.g.10), and each having a greater length in the longitudinal direction ofthe conveyor belt than each link member; wherein each product carrier(17) includes a plurality of rigid elements (18) which are articulated(19) to each other transversely to the longitudinal direction of theconveyor belt (1), whereby the product carrier is permitted to movetogether with the conveyor belt about the guide roller (e.g. 10).
 21. Anendless conveyor belt movable about a guide roller transverse to alongitudinal direction of the conveyor belt; the conveyor beltcomprising:a plurality of interconnected link members (2), the conveyorbelt (1) being movable along a curved path (22) a plurality of productcarriers (17), which are successively supported upon the link members(2), are essentially rigid in the plane of the conveyor belt (1), whichare movable together with the conveyor belt about the guide roller (e.g.10), and each having a greater length in the longitudinal direction ofthe conveyor belt than each link member; wherein the length of eachproduct carrier (17) in the longitudinal direction of the conveyor beltis at least as great as a length of two link members; and wherein eachproduct carrier (17) is connected to a link member thereof in a part ofthe product carrier which is frontal in a direction of travel of theconveyor belt (1).